voxl-vision-px4 crashing potentially when px4 cpu load too high

[benjamin linne]

Steps To Reproduce:

1. Connect to uas over wireless connection
2. Run top in MAVLink Console and wait a couple minutes
3. Top will eventually freeze.
4. Observe systemctl status voxl-vision-px4 outputs WARNING PX4 DISCONNECTED FROM UART
5. Attempt systemctl restart voxl-vision-px4 and voxl freezes
6. Only way to fix is a hard reboot

Additional Context:
Running the latest px4 release 1.12 beta5. I also think this behavior can be observed in 1.11. The main issue with 1.12 is the cpu load is significantly higher and I suspect delays in the mavlink processing causes px4-voxl-vision to crash.

[benjamin linne]

A faster way to replicate is in the MAVLink Console send reboot then hit enter a second later for the shell to reappear then send top and a few seconds later it completely freezes up and requires a hard reboot.

[Chad Sweet]

A few things to try:

• Set governor to conservative https://docs.modalai.com/thermal-and-performance/#governor
• Set mav_1_mode set to normal or minimal
• Try using voxl-cpu-monitor to monitor the usage (better than top)

Which version of voxl-vision-px4 are you using?

• There is a known mavlink packet to cause a crash. The dev branch of vvpx4 has this fixed.

[James Strawson]

This is a known bug that was fixed in voxl-vision-px4 v0.8.8 which is currently on the development repo, scheduled to be merged into the stable repo in a week or so.

The bug is not caused by PX4, it was due the the handling of the specific mavlink packet containing console data. It should behave normally when not using the PX4 console.